INFLUENCE OF IONIC SALT COMPOSITION OF SOIL SOLUTION ON MICROAGGREGATE DISINTEGRATION IN CALCAREOUS CHERNOZEM

Laboratory experiments with Calcareous Chernozems showed that changes in salt composition cause disintegration of microaggregates (> 0.01 mm ) while inducing no reliable increase of the content of nonaggregated particles (< 0.001 mm). SAR and the specific electrical conductivity o f the soil solution have the most important influences on microstructu re disintegration. Magnesium caused marked disaggregation only when it was the dominant bivalent cations (> 60-70 percent). Change in ionic salt composition on the background of mechanical mixing of moist soil promotes more profound disintegration of the initial soil microstructu re.